Understanding Zoonotic Spillovers and Emerging Viral Threats
Zoonotic spillover occurs when a virus crosses from animals to humans. Understanding these events helps predict future outbreaks and supports global health preparedness.
What Is a Spillover Event?
1.Virus exists in an animal reservoir
2.Human exposure occurs
3.The virus adapts and infects humans
Why Spillovers Are Increasing
– Increased contact between humans and wildlife
– Deforestation and environmental disruption
– Expansion of global travel
– Climate-driven ecological changes
Key Stages of Viral Emergence
1. Animal reservoir
2. Exposure to humans
3. Initial infection
4. Human-to-human transmission
5. Community spread or outbreak
Related Reading: Electron Microscopy Gallery of Zoonotic Viruses (included below).
This gallery contains simplified descriptions of EM-style viral representations used for education in the ‘Emerging Zoonotic Viruses’ series.
Langya Virus (LayV)

– Reservoir: Shrews
– Causes fever, fatigue, and multi-organ involvement
Nipah Virus

– Reservoir: Fruit bats
– Causes severe encephalitis
Hendra Virus

– Reservoir: Bats → Horses → Humans
– Severe respiratory and neurological disease
Kiwira Virus

– Reservoir: Bats
– Emerging arenavirus with evolving clinical understanding
SARS-like Coronaviruses

– Reservoir: Bats
– Potential for spillover under certain conditions
Disclaimer
mages associated with this gallery are representative illustrations and should not be treated as diagnostic EM micrographs. They serve an educational purpose only.